The rating of perceived exertion predicts intermittent vertical jump demand and performance

The aims of this study were (a) to assess the ability of the rating of perceived exertion (RPE) to predict performance (i.e. number of vertical jumps performed to a fixed jump height) of an intermittent vertical jump exercise, and (b) to determine the ability of RPE to describe the physiological demand of such exercise. Eight healthy men performed intermittent vertical jumps with rest periods of 4, 5, and 6 s until fatigue. Heart rate and RPE were recorded every five jumps throughout the sessions. The number of vertical jumps performed was also recorded. Random coefficient growth curve analysis identified relationships between the number of vertical jumps and both RPE and heart rate for which there were similar slopes. In addition, there were no differences between individual slopes and the mean slope for either RPE or heart rate. Moreover, RPE and number of jumps were highly correlated throughout all sessions (r = 0.97-0.99; P < 0.001), as were RPE and heart rate (r = 0.93-0.97; P < 0.001). The findings suggest that RPE can both predict the performance of intermittent vertical jump exercise and describe the physiological demands of such exercise.     

Impaired motor control after sport-related concussion could increase risk for musculoskeletal injury: Implications for clinical management and rehabilitation

This review presents a conceptual framework and supporting evidence that links impaired motor control after sport-related concussion(SRC)to increased risk for musculoskeletal injury.Multiple studies have found that athletes who are post-SRC have higher risk for musculoskeletal injury compared to their counterparts.A small body of research suggests that impairments in motor control are associated with musculoskeletal injury risk.Motor control involves the perception and processing of sensory information and subsequent coordination of motor output within the central nervous system to perform a motor task.Motor control is inclusive of motor planning and motor learning.If sensory information is not accurately perceived or there is interference with sensory information processing and cognition,motor function will be altered,and an athlete may become vulnerable to injury during sport participation.Athletes with SRC show neuroanatomic and neurophysiological changes relevant to motor control even after meeting return to sport criteria,including a normal neurological examination,resolution of symptoms,and return to baseline function on traditional concussion testing.In conjunction,altered motor function is demonstrated after SRC in muscle activation and force production,movement patterns,balance/postural stability,and motor task performance,especially performance of a motor task paired with a cognitive task(i.e.,dual-task condition).The clinical implications of this conceptual framework include a need to intentionally address motor control impairments after SRC to mitigate musculoskeletal injury risk and to monitor motor control as the athlete progresses through the return to sport continuum.     

Physiological and metabolic responses of wheelchair athletes in different racing classes to prolonged exercise

The aims of this study were to examine and compare selected physiological and metabolic responses of wheelchair athletes in two paraplegic racing classes [T3: n = 8 (lesion levels T1-T7; paraplegics); T4: n = 9 (lesion levels below T7; paraplegics)] to prolonged exercise. In addition, we describe the responses of three tetraplegic athletes [T2: n = 3 (lesion levels C6/C7: tetraplegics)]. Twenty athletes completed 90 min of exercise at 75% VO2peak on a motorized treadmill adapted for wheelchairs. The mean (+/- s) heart rates of the T3 and T4 racing classes were 165 +/- 2 and 172 +/- 6 beats.min-1, respectively. For the T4 racing class, heart rate gradually increased during the test (P < 0.05), whereas for the T3 racing class, heart rate reached a plateau after an initial increase. The mean heart rate of the tetraplegics was 114 +/- 3 beats.min-1. The T3 and T4 classes exhibited similar respiratory exchange ratios, plasma lactate and glucose concentrations throughout the test. For both the T3 and T4 racing class, free fatty acid, glycerol, ammonia, urea and potassium concentrations had increased from resting values by the end of the test (P < 0.05). In conclusion, the results of this study suggest that endurance-trained wheelchair athletes are able to maintain velocities equivalent to the same relative exercise intensity (75% VO2peak) for prolonged periods irrespective of lesion level.     

“原谅我这一生不羁放纵爱自由” 行走在刃脊——致中国技术型登山的开拓者(?)一桦和他的搭档美国人JON OTTO

总有那样的人,是不甘于平庸的；也总有那样的人,永远不肯驻足。在远方,在路上,一直是他们生活的理想。在做这期户外运动的特别策划时,我们脑子里一直在萦绕着Beyond的那一首《海阔天空》：今天我寒夜里看雪飘过怀著冷却了的心窝飘远方风雨里追赶雾里分不清影踪天空海阔你与我可会变(谁没在变)多少次迎著冷眼与嘲笑从没有放弃过心中的理想一刹那恍惚若有所失的感觉不知不觉已变淡心里爱(谁明白我)原谅我这一生不羁放纵爱自由也会怕有一天会跌倒背弃了理想谁人都可以那会怕有一天只你共我仍然自由自我永远高唱我歌我们写了他们,写了热爱自由热爱行走的他们；我们也期待你,跃跃欲试身未动心却先行的你,加入到这样的行列。原谅我这一生不羁放纵爱自由’,我们的特别策划,献给所有这样的你,你们。     

Stress analysis of anisotropic thick laminates in cylindrical bending using a semi-analytical approach

Semi-analytical elasticity solutions for bending of angle-ply laminates in cylindrical bending are presented using the state-space-based differential quadrature method (SSDQM). Partial differential state equation is derived from the basic equations of elasticity based on the state space concept. Then, the differential quadrature (DQ) technique is introduced to discretize the longitu- dinal domain of the plate so that a series of ordinary differential state equations are obtained at the discrete points. Meanwhile, the edge constrained conditions are handled directly using the stress and displacement components without the Saint-Venant principle. The thickness domain is solved analytically based on the state space formalism along with the continuity conditions at interfaces. The present method is validated by comparing the results to the exact solutions of Pagano’s problem. Numerical results for fully clamped thick laminates are presented, and the influences of ply angle on stress distributions are discussed.     

The impact of a dialogic reading program on deaf and hard-of-hearing kindergarten and early primary school-aged students in Hong Kong

The present study investigated the effects of a special interactive dialogic reading method developed by Whitehurst et al. (1988) on deaf and hard-of-hearing children in Hong Kong. Twenty-eight deaf and hard-of-hearing children in kindergarten, first, or second grade were pretested on a receptive vocabulary test and assigned to one of three conditions, dialogic reading, typical reading, and control, with age and degree of hearing loss matched. After an 8-week intervention, the children were re-tested. The dialogic reading group had a significantly greater improvement in vocabulary scores than did the other two groups. Parent-child interactions of high quality and the use of pictorial materials are likely the key successful factors in the program. The educational value of this intervention is discussed.     

Relation between reading problems and internalizing behavior in school for preadolescent children from economically disadvantaged families

This longitudinal study of 105 economically disadvantaged children examined the relation between reading problems and internalizing behavior in 3rd- and 5th-grade assessments (8- to 12-year olds). The variable-centered results showed that reading problems predicted change in internalizing behavior in the context of child and family predictors. The person-centered results showed that children with reading problems in both grades had higher internalizing scores in 5th grade but not in 3rd grade than children with reading problems in 3rd grade or no problems. Child-reported negative emotion experiences varied similarly across grade. The results tie reading problems to emotional distress in school and support conclusions about the direction of effects and the internalization of academic difficulty for disadvantaged children.     

A randomized controlled trial of a home-visiting intervention aimed at preventing relationship problems in depressed mothers and their infants

This study examined the effect of a mother–baby intervention on the quality of mother–child interaction, infant–mother attachment security, and infant socioemotional functioning in a group of depressed mothers with infants aged 1–12 months. A randomized controlled trial compared an experimental group ( n = 35) receiving the intervention (8–10 home visits) with a control group ( n = 36) receiving parenting support by telephone. There were assessments pre, post, and follow-up after 6 months. The intervention had positive effects on the quality of mother–infant interaction. Infants in the experimental group had higher scores for attachment security and for one aspect of socioemotional functioning, namely, competence. The intervention proved successful in preventing deterioration of the quality of mother–child interaction.     

Social working memory: Memory for another rat's spatial choices can increase or decrease choice tendencies

In two experiments using a radial-arm maze, pairs of rats made choices among eight maze locations, each containing a large quantity of one of two food types. The choices made by 1 rat affected the choices made by the other rat. Under most conditions, visits by 1 rat increased the tendency of the other rat to subsequently choose that maze location. However, the effect depended on the quality of the food available in a particular location. When it was possible for the rats to observe each other on the maze arms and a rat had experienced that a location contained the less preferred food type, a previous visit to that location by the foraging partner decreased the tendency to visit that location. These effects are attributed to working memory for the spatial choices of another rat, and they indicate that memory produced by a rat’s own visit to a maze location is integrated with memory for the behavior of another rat to determine spatial choice     

History of childhood abuse in Portuguese parents

OBJECTIVE: The study examines the self-reported prevalence of childhood physical and sexual abuse in a large sample of Portuguese parents. METHOD: Nearly 1,000 parents (506 mothers and 426 fathers) were selected through public primary schools from the Northern area of Portugal. All completed the Portuguese version of the Childhood History Questionnaire (CHQ) [Journal of Family Violence 5 (1990) 15]. RESULTS: Results show that the prevalence of abuse was 73%, but more severe physical abuse involving sequelae/injury was reported by 9.5%. Most physical abuses began prior to age 13, with half continuing after age 13. No gender differences were found for rates of physical abuse. However, among the milder physical abuse without sequelae/injury, those women who experienced "whipping" or "slapping/kicking" were more likely to do so from their mothers than fathers. Among men who were "slapped/kicked" this was more likely to be from their fathers. Low rates of sexual abuse were found at 2.6% with no gender or age differences. Lack of a supportive adult in childhood related to the more severe abuses, but only in adolescence. Portuguese rates of abuse were consistently lower than those reported in USA and Spanish studies using the CHQ. CONCLUSIONS: This is the first retrospective, self-report study of childhood abuse in a large sample of Portuguese parents and, even with a participation rate of 69%, shows lower rates than in US and Spanish samples.